It’s one of the most famous inscriptions in American life: “Neither snow nor rain nor heat nor gloom of night stays these couriers from the swift completion of their appointed rounds.” And it’s something in which Americans have an unspoken faith: If you put a stamp on a letter and drop it in the mail, it will arrive at its destination.

But what if a postal employee refused to deliver a letter? (It’s happened in real life: A mail courier made national headlines – and lost his job – a year ago for failing to inflict junk mail on the houses on his route.) That’s the nominal setup of Sarah Blake’s new novel The Postmistress, although it takes almost 250 pages for this moral dilemma to pop up.

Until then, Blake traces the lives of three women in the months leading up to the United States’ involvement in World War II. One is the titular postmistress, one is a newly married doctor’s wife, and one is a radio reporter covering the Blitz under the tutelage of Edward R. Murrow. Can you doubt that the paths of these three are going to intertwine in life-changing ways? If so, you’ve never read a historical novel.

“The Postmistress” examines the question of truth-telling in wartime, and the fact that we can never learn the whole story, as the reporter takes her recorder on trains across Europe, interviewing the last wave of Jewish refugees trying to get out before the exits slam shut. The vitality inherent in that vocal record, fragmentary though it of necessity is, is the most resonant part of the novel.